Split-structure skis

ABSTRACT

A ski in which the structure, rather than being an entity as in the conventional skis, is split into two parallel runners and an overlying binding portion. The runners are linked to the binding portion by elastically reacting links so that each runner can be vertically shifted with respect to the other runner and vice versa. The elastic reaction can be provided by a hydraulic fluid or a mechanical linkage. With the suggested arrangement, an improved stability of the ski in its path is warranted inasmuch as the ski edge can more efficiently act upon the snowy ground.

United States Patent 1 Locati 5] Nov. 25, 1975 1 SPLIT-STRUCTURE SKIS 22 Filed: May2, 1974 211 Appl. No.: 466,469

[30] Foreign Application Priority Data May 2. 1973 Italy 23631/73 [52] U.S. Cl. 280/11.l3 W; 280/21 A [51] Int. Cl. A63C 5/00 [58] Field of Search280/ll.13 S, 11.13 W, 11.13 F.

280/11.l3 A, 11.13 R, 11.14, 11.15, 11.37 E,

11.37 R, 21 A; 9/310 AA France 280/11.13 S

Austria 280/1 1.13 S

Primary Examinerl(enneth l-l. Betts Assistant Examiner-Milton L. Smith Attorney, Agent, or Firm-Cushman, Darby & Cushman 57 I ABSTRACT A ski in whichthe structure, rather than being an entity as in the conventional skis, is split into two parallel runners and an overlying binding portion. The runners are linked to the binding portion by elastically reacting links so that each runner can be vertically shifted with respect to the other runner and vice versa. The elastic reaction can be provided by a hydraulic fluid or a mechanical linkage. With the suggested arrangement, an improved stability of the ski in its path is warranted inasmuch as the ski edge can more efficiently act upon the snowy ground.

6 Claims, 9 Drawing Figures Elsi U.S. Patent Nov. 25, 1975 Sheet2of4 3,921,994

U.S. Patent Nov. 25, 1975 Sheet30f4 I 3,921,994

US. Patent N0v.25, 1975 Sheet4of4 3,921,994

SPLIT-STRUCTURE SKIS It is known that in the use of skis the steering capability is mostly entrusted to the action of the edges of the ski sole on the snow.

For example, when a skier goes down-hill along an oblique course, the skis permit to hold the path as desired if the upward edges press the snow with a sufficient force: as a matter of fact the ski held with its sole entirely resting on the snow with a uniform pressure could not afford a sufficient hold on the sides, and would thus skid sideways. The skier prevents this possibility by applying his weight on the edge which is upwards with an appropriate posture of the body and a correct action of the legs.

Similar effects are experienced when the skier has to go along a turn; once the turn has been negotiated with an appropriate distribution of the weight, the skis have to carry out an appropriately controlled sliding motion so as to arrange themselves sequentially in positions of tangency to the curved path they have to go along.

In general, anyhow, a ski which is not guided to go along a planar rectilinear path acts upon the snow with one of its edges: in fact, these are formed by steel strips to withstand the wear and to get a good hold on the snow.

The present invention has the purpose of improving the resistance of a ski to the sideways skid so as to permit a more convenient directional control by the skier.

According to the invention a ski comprises a binding portion to which the ski boot is to be fastened, and a sliding portion, formed by at least two runners placed side by side and connected to the binding portion with links which allow the relative motion of at least the central parts of the runners.

In order that the functional and structural features of the ski according to the invention may be better understood, an exemplary embodiment thereof will now be described, to be illustrated in the accompanying drawings, wherein:

FIGS. 1 and 2 are general diagrammatical views, in elevation and in plan view, respectively, of a ski ac-- cording to the invention.

FIG. 3 is a plan view of a detail of the ski of FIG. 1.

FIG. 4 is a cross-sectional view taken along the line IV-IV of FIG. 3.

FIG. 5 is a cross-sectional view taken along the line VV of FIG. 4.

FIGS. 6 and 7 are a plan view and an elevational view, respectively, of a different detail of the ski of FIG. 1

FIG. 8 is a view similar to that of FIG. 3, and shows a constructional modification of a detail of the ski, and

FIG. 9 is a cross-sectional view taken along the line IX-IX of FIG. 8.

The ski as shown in FIGS. 1 and 2 comprises two side-by-side runners 10 and 11, connected by couplings l2 and 13 to a plate 14. On the latter, a ski boot 16 is fastened with any conventional ski-binding 15.

The binding portion as generally shown at 12 is better shown in FIGS. 3, 4 and 5. It comprises a base block 17 to which a plate 14 is hinged at 18. Within the block cylindrical seats 19 and 20 are formed in which pistons 21 and 22 are movable, to whose stems 23 and 24 are locked plates 25 and 26, affixed with screws 27 to the runners 10 and 11. The chambers as defined by the pistons 21 and 22 within the respective seats 19 and 20 are 2 filled with a fluid and connected to one another by a duct 28, whose aperture can be throttled by an adjusting screw 29.

The unit 13 is the mirror image of the unit 12 so that it will not be described in detail.

The runners 10 and 11 are linked to one another in the vicinity of their front ends by a sliding coupling: to the runner 10 an angle iron 30 is applied, which carries a head 31 slidable within the guideway 32 as affixed to the runner 11.

The operation of the ski as described can easily be understood from the Figures which illustrate it.

FIGS. 4 and 5 show the trim as taken by the ski when it goes along an oblique course downhill; the profile of the ground is diagrammatically shown at 33.

It is apparent that an upward movement of the piston 21 corresponds to a downward movement of the piston 22: this movement can be braked by throttling the duct 28 through which the fluid displaced from the seat 19 to the seat 20 flows. On the slope 33 thus rests the upward edge of each of the runners l0 and 11 which are held horizontal if the skiers ankle keeps the resting plate 14 horizontal. The force that the skier should exert to maintain such a horizontal trim is obviously less than the force which is required to maintain a conventional ski virtually horizontal, the central resting edge being not provided in such a ski. The simultaneous resting of the two edges, in addition, provides a holding action against the sideways skid, said action being very efficient, and permits to have a better hold on the ground.

The behaviour of the ski in a turn is under many respects similar to that discussed in connection with an oblique downhill course run: as a matter of fact an inclination of the plate 14 towards the interior of the turn, as carried out by the skier, brings into engage- I ment the two edges of the runners 10 and 11 which are at the interior of the turn. The result is thus obtained of controlling in a very efficient manner the sideways skid of the ski and thus the desired curved path can be travelled over.

The additional link between the runners, as formed by the head 31 freely slidable within the guideway 32, allows a parallel movement of the runners, but prevents the ski tips from spreading apart: this link, which is not essential as itself, increases both the reliability and the stability of the path of the ski, even on very irregular surfaces.

The embodiment as described herein is merely exemplary, as indicated above. For example the link between the runners can also be embodied by a merely mechanical linkage, as shown in FIG. 8. There is shown a linking unit 112, wholly similar to the unit 12 of FIG. 4 and similar parts are indicated with the same reference numeral to which the FIG. 1 is applied as a prefix.

In the unit 112 two sliders 122 and 123 are movable in seats 1 19 and and carry pins and 141 which engage slots 142 and 143 of the lever 144, freely oscillable at 145.

Obviously, the rocker 144 fulfils the task of the fluid contained in the seats 19 and 20 of the unit 12.

The damping effect as obtained with the throttling of also mechanisms can be considered, which perform a motion of the runners which is not rigorously parallel, neither between the two runners, nor between the runners and the plate 14. For example, a mechanism can be provided which arranges the runners, when they are vertically staggered, parallel to one another but lying with their soles on planes which are not parallel to the plane containing the plate 14. By so doing, it becomes possible to vary the posture of the edge which is intended to rest on the ground, until obtaining an optimum value of path holding.

In the embodiment shown herein there has been described a ski in which the two runners are thoroughly separated: it is however possible that they are separated in the central area only, that is, they are integral with one another at the tip and the tail, or in one of theselatter only.

The ski has been described as to its general structure according to the invention. However, constructional details common to the conventional skis have not been described: for example each of the skis could have at the sole edges metal strips to make a biting edge: the structure and the materials which make up the runners can then be those which are used in the conventional ski making art.

The embodiment as described comprises two side-byside runners: if it is deemed appropriate, a ski can be made which is entirely similar but having more than two runners, for example three. An advantageous embodiment of such a ski comprises for example three hydraulic rams moving in the bodies 12 and 13, whose working chambers are interconnected by ducts: also in this case purely mechanical linkages can be provided.

It should be noticed, lastly, that the hinges 18 have proven to be adapted, in the practice, to prevent the stiffening of the central portion of the ski, due to the superposition of the runners and the plate 14, thus impeding that a rigid parallelogram might be formed: however, appropriate degrees of freedom as left in the connection between the plate 14 and the units 12 and 13 and between these latter and the runners and 11, will enable the same result to be obtained with different means.

. What is claimed is:

1. A ski comprising a binding portion, to which a ski boot of a skier is intended to be fastened, and a sliding runners to move with respect to each other perpendicularly to the sliding plane of the sliding body.

2. A ski according to claim 1, wherein said runners carry mutual connections in correspondence with their tip and/or tail portions.

3. A ski according to claim 2, wherein said connections permit a mutual relative vertical movement of the mutually connected parts.

4. A ski according to claim 1 wherein the linkage means connects said runners to said binding portion so that a movement of one runner with respect to the binding portion causes a substantially equal and oppositely directed movement of the other runner with respect to said binding portion.

5. A ski according to claim 4, wherein said linkage means comprises pistons located on an upper portion of each of said runners, said pistons being located adjacent said binding portion and corresponding seats integral with said binding portion, each of said pistons being movably positioned within said seats so as to de- 7 fine a compression chamber therein, said compression chamber formed by each piston in its seat being occupied by a fluid and communicating with the compression chamber formed in its seat by the corresponding piston of the other runner.

6. An improved ski comprising: individual first and second sliding body portions each having a bottom surface for slidably engaging snow and defining a sliding plane, a binding portion to which a boot of a skier can be fastened, linkage means for individually connecting each of said first and second sliding body portions to said binding portion so that a slot is formed between said first and second sliding body portions, said first and second portions being movable with respect to each other and perpendicularly with respect to the sliding plane. 

1. A ski comprising a binding portion, to which a ski boot of a skier is intended to be fastened, and a sliding body provided with at least one longitudinal slot which at least partially divides it into two side-by-side runners, linkage means for individually connecting each runner to said binding portion in such manner as to allow said runners to move with respect to each other perpendicularly to the sliding plane of the sliding body.
 2. A ski according to claim 1, wherein said runners carry mutual connections in correspondence with their tip and/or tail portions.
 3. A ski according to claim 2, wherein said connections permit a mutual relative vertical movement of the mutually connected parts.
 4. A ski according to claim 1 wherein the linkage means connects said runners to said binding portion so that a movement of one runner with respect to the binding portion causes a substantially equal and oppositely directed movement of the other runner with respect to said binding portion.
 5. A ski according to claim 4, wherein said linkage means comprises pistons located on an upper portion of each of said runners, said pistons being located adjacent said binding portion and corresponding seats integral with said binding portion, each of said pistons being movably positioned within said seats so as to define a compression chamber therein, said compression chamber formed by each piston in its seat being occupied by a fluid and communicating with the compression chamber formed in its seat by the corresponding piston of the other runner.
 6. An improved ski comprising: individual first and second sliding body portions each having a bottom surface for slidably engaging snow and defining a sliding plane, a binding portion to which a boot of a skier can be fastened, linkage means for individually connecting each of said first and secOnd sliding body portions to said binding portion so that a slot is formed between said first and second sliding body portions, said first and second portions being movable with respect to each other and perpendicularly with respect to the sliding plane. 